I do know that the blades on a propeller generate lift to provide a force pushing back on the air based on newton's law the 2nd. What I am having trouble understanding is how the blades generate thrust by cutting through the air? I know that helicopter hover because they push air downwards, but on a propeller the angle of the blades is much different than of a helicopters blades. Also I don't understand a zero lift configuration. I am having a lot of trouble understanding how helicopters push air downwards, as you can see in this picture
The airfoil doesn't look at all like it can push air downwards. I hope you guys can understand my confusion with this subject. Also I have looked this up on google and was provided answers that were way too confusing for me to understand, so can you give me an answer that is easy to understand. Thanks.